package leetcode._0217;
import java.util.HashSet;

/**
 * 217. Contains Duplicate
 * Easy
 *
 * 494
 *
 * 578
 *
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 *
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 * Given an array of integers, find if the array contains any duplicates.
 *
 * Your function should return true if any value appears at least twice in the array, and it should return false if every element is distinct.
 *
 * Example 1:
 *
 * Input: [1,2,3,1]
 * Output: true
 * Example 2:
 *
 * Input: [1,2,3,4]
 * Output: false
 * Example 3:
 *
 * Input: [1,1,1,3,3,4,3,2,4,2]
 * Output: true
 */
public class Solution {
    public boolean containsDuplicate(int[] nums) {
        HashSet<Integer> hashSet = new HashSet<>();
        for (int i = 0; i < nums.length; i++) {
            if (!hashSet.contains(nums[i])){
                hashSet.add(nums[i]);
            } else {
                return true;
            }
        }
        return false;
    }
}
